BIODEGRADABLE POLYMERS & ITS APPLICATIONS IN PHARMACEUTICS : 1-19 BIODEGRADABLE POLYMERS & ITS APPLICATIONS IN PHARMACEUTICS Made By:
H.R. PATEL INSTITUTE OF PHARMACEUTICAL
EDUCATION & RESEARCH CENTER, SHIRPUR :CONTENTS: : 2 :CONTENTS: 1. Introduction2
2. Need of Biodegradable polymers3,4
4. Degradation Scheme3,4
5. Mechanism of Polymerization2
6. Applications,1,2,3 Biodegradable polymers : 3 Biodegradable polymers Polymers: macromolecule consisting of large number of monomers.
Definition: Polymers degraded by biological means such as enzymes,micro-organisms.
1) Natural polymers
2) Synthetic polymers Why Would a Medical Practitioner Like a Material to Degrade in the Body? : 4 Why Would a Medical Practitioner Like a Material to Degrade in the Body? Do not require a second surgery for removal
Avoid stress shielding
Offer tremendous potential as the basis for controlled drug delivery Mechanical Strength A) NATURAL POLYMERS : 5 A) NATURAL POLYMERS A) Proteins B) Polysaccharides
1. Albumin 1. Starch
2. collagen 2. Hyaluronic acid
3. Gelatin 3. Dextran
4. Alginic acid
5. Xanthan Gum
6. Guar Gum
11. Cyclodextrin B) Synthetic polymers : 6 B) Synthetic polymers Polyesters:
eg. PLA, PGA, Poly hydroxy butyrate (PHB),Poly-e- caprolactone(PCL),Polymalic acid,Polydioxanone(PDA)
eg. Poly sebacic acid (PSBA), poly adipic acid (PAPA), Poly terphthalic acid (PTA)
eg. Poly imino carbonate (PIC),
Poly amino acid (PAA) Slide 7: 7 4. Phosphorus Based :
5. Others :
eg. Polycyanoacrylates (PCA),
Polyacetals. Why We Prefer Synthetic polymers than natural one Ones? : 8 Why We Prefer Synthetic polymers than natural one Ones? Tailor-able properties
Predictable lot-to-lot uniformity
Free from concerns of immunogenicity
Reliable source of raw materials Degradation Schemes : 9 Degradation Schemes Degradation
An irreversible process leading to a significant change of the structure of a material, typically characterized by a loss of properties, such as integrity, molecular weight, structure or mechanical strength, into a product easily eliminated by the body metabolic pathway
Degradation may be by :
1) chemical means or
2) Physical means CHEMICAL DEGRADATION3 : 10 CHEMICAL DEGRADATION3 Chemical changes occurs in polymers which includes cleavage of covalent bonds, hydrolysis, ionization or protonation either along the back bone or side chains of polymers.
Chemical degradation leads to the change in molecular weight or solubility of polymer. PHYSICAL EROSION MECHANISM4 : 11 PHYSICAL EROSION MECHANISM4 (A) Bulk-eroding system
Degradation takes place throughout the whole of the polymer matrix.
Loss of physical integrity.
Ingress of water is faster than the rate of degradation
(B) Surface-eroding system
(poly(ortho)esters and polyanhydrides)
Eroded from the surface
Physical integrity maintained
Mass loss is faster than the ingress of water into the bulk Slide 12: 12 Polymer Degradation by Erosion3 MECHANISM OF POLYMERISATION2 : 13 MECHANISM OF POLYMERISATION2 There are two types of polymerization methods reported
These polymerizations are also known as Vinyl polymerization because most of the monomers of interest are compounds that contains a vinyl group .
In general chain polymerization is done by following four types according to the nature of active center
Free radical ,
Anionic chain polymerization ,
Cationic polymerization and
Ziegler- Natta polymerization . Slide 14: 14 B. Step growth polymerization:-
It is any two species in the reaction mixture can react by specific reaction between two appropriate functional groups
A polymerization mechanism in which each reaction between monomers is a discrete and independent step. MEDICAL APPLICATIONS OF BIODEGRADABLE POLYMERS4, : 15 MEDICAL APPLICATIONS OF BIODEGRADABLE POLYMERS4, Wound management
Tissue engineering Dental applications
Guided tissue regeneration Membrane
Void filler following tooth extraction
Drug delivery system Some Individual applications of Biodegradable polymers : 16 Some Individual applications of Biodegradable polymers Slide 17: 17 references : 18 references 1) Pal O.P. Malviya R.,Bansal V.,Sharma P.K., Rosin an important polymer for drug delivery”,”international journal of pharmaceutical sciences”,volume-3,issue-1,july-aug-2010,article 007,P.no.35-36.
2) Jain N.K.,”Pharmaceutical Product Development”,First edition,CBS publication,P.N.585-621.
3) www.biodeg.net/Biodegradable polymers
4)www.bioen.utah.edu/faculty/pat/.../Biodegradable%20Materials.ppt THANKING YOU : 19 THANKING YOU